Zipf, David Glenn.

This project addresses the simulation, control and optimization of underwater vehicle performance. An analytical model of underwater vehicle motion has been developed. This model is based on a set of six degree of freedom nonlinear differential equations of motion. These equations incorporate inertial, hydrodynamic, hydrostatic, gravity and thruster forces to define the vehicle's motion. The forces are calculated and the equations of motion solved using a finite difference method of integration. An automatic closed loop control strategy has been developed and integrated into the motion model. The controller determines control plane deflection and thruster output based on sensor provided input, maneuver request and control gain constants. The motion model simulates the effects of these controller requests on the vehicle motion. The controller effects are analyzed and an optimal set of control gains is determined. These optimal gains are determined based on a quantitative comparison of a pre-defined Performance Index (PI) function. The PI is a function of critical performance values, i.e., energy consumption, and user defined weighted constants. By employing an iteration technique the PI is minimized to provide an optimal set of control gains.